U.S. patent number 8,552,239 [Application Number 13/255,239] was granted by the patent office on 2013-10-08 for olefin production process.
This patent grant is currently assigned to Mitsui Chemicals, Inc.. The grantee listed for this patent is Terunori Fujita, Kenji Fujiwara, Masayasu Ishibashi, Tsuneyuki Ohkubo. Invention is credited to Terunori Fujita, Kenji Fujiwara, Masayasu Ishibashi, Tsuneyuki Ohkubo.
United States Patent |
8,552,239 |
Ohkubo , et al. |
October 8, 2013 |
Olefin production process
Abstract
A novel olefin production process is provided which can be
established as an industrial and practical process capable of
producing olefins by directly reacting a ketone and hydrogen in a
single reaction step. In particular, a novel olefin production
process is provided in which propylene is obtained with high
selectivity by directly reacting acetone and hydrogen. The olefin
production process according to the present invention includes
reacting a ketone and hydrogen in the presence of at least one
dehydration catalyst and a silver-containing catalyst, and the at
least one dehydration catalyst is selected from metal oxide
catalysts containing a Group 6 element, zeolites, aluminas and
heteropoly acid salts in which part or all the protons in
heteropoly acids are exchanged with metal cations.
Inventors: |
Ohkubo; Tsuneyuki (Ichihara,
JP), Fujiwara; Kenji (Kamakura, JP),
Fujita; Terunori (Yokohama, KR), Ishibashi;
Masayasu (Iwakuni, JP) |
Applicant: |
Name |
City |
State |
Country |
Type |
Ohkubo; Tsuneyuki
Fujiwara; Kenji
Fujita; Terunori
Ishibashi; Masayasu |
Ichihara
Kamakura
Yokohama
Iwakuni |
N/A
N/A
N/A
N/A |
JP
JP
KR
JP |
|
|
Assignee: |
Mitsui Chemicals, Inc. (Tokyo,
JP)
|
Family
ID: |
42739626 |
Appl.
No.: |
13/255,239 |
Filed: |
March 12, 2010 |
PCT
Filed: |
March 12, 2010 |
PCT No.: |
PCT/JP2010/054169 |
371(c)(1),(2),(4) Date: |
September 07, 2011 |
PCT
Pub. No.: |
WO2010/106966 |
PCT
Pub. Date: |
September 23, 2010 |
Prior Publication Data
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|
|
|
Document
Identifier |
Publication Date |
|
US 20120010453 A1 |
Jan 12, 2012 |
|
Foreign Application Priority Data
|
|
|
|
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Mar 16, 2009 [JP] |
|
|
2009-062686 |
|
Current U.S.
Class: |
585/638; 502/348;
502/347 |
Current CPC
Class: |
C07C
1/24 (20130101); B01J 29/7815 (20130101); B01J
23/30 (20130101); B01J 35/0006 (20130101); C12P
7/28 (20130101); B01J 23/002 (20130101); B01J
23/66 (20130101); B01J 37/04 (20130101); B01J
29/068 (20130101); B01J 27/188 (20130101); B01J
23/50 (20130101); C12P 7/04 (20130101); B01J
23/687 (20130101); B01J 29/7415 (20130101); C07C
1/24 (20130101); C07C 11/06 (20130101); C07C
2523/28 (20130101); C07C 2523/30 (20130101); B01J
2523/00 (20130101); C07C 2527/188 (20130101); C07C
2527/182 (20130101); B01J 2229/20 (20130101); C07C
2521/04 (20130101); C07C 2521/08 (20130101); Y02P
20/52 (20151101); B01J 2523/00 (20130101); B01J
2523/18 (20130101); B01J 2523/33 (20130101); B01J
2523/41 (20130101) |
Current International
Class: |
C07C
1/20 (20060101) |
Field of
Search: |
;585/638,639,640,641,642,422,446
;568/798,799,768,385,565,569,577,741 ;502/60-71 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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1043956 |
|
Jul 1990 |
|
CN |
|
84378 |
|
Sep 1971 |
|
DE |
|
1 974 812 |
|
Oct 2008 |
|
EP |
|
61-067493 |
|
Apr 1986 |
|
JP |
|
02-174737 |
|
Jul 1990 |
|
JP |
|
03-041035 |
|
Feb 1991 |
|
JP |
|
03-041038 |
|
Feb 1991 |
|
JP |
|
06-091171 |
|
Apr 1994 |
|
JP |
|
2008-513449 |
|
May 2008 |
|
JP |
|
WO 02/066407 |
|
Aug 2002 |
|
WO |
|
WO-2009/008377 |
|
Jan 2009 |
|
WO |
|
Other References
Vazquez et al. "Silica Supported Heteropolyacids as Catalysts in
Alcohol Dehydration Reactions." Journal of Molecular Catalysis A:
Chemical 161 (2000) 223-232. cited by examiner .
Bermejo, Lourdes L. et al., "Expression of Clostridium
acetobutylicum ATCC 824 Genes in Escherichia coli for Acetone
Production and Acetate Detoxification," Applied and Environmental
Microbiology, Mar. 1998, vol. 64, No. 3, pp. 1079-1085. cited by
applicant .
International Search Report mailed Jun. 22, 2010 in International
Application No. PCT/JP2010/054169. cited by applicant .
Russian Office Action for Application No. 2011126629/(039472),
dated Feb. 8, 2012 with English translation. cited by applicant
.
Written Opinion and Search Report Singapore Application No.
201103938-5 dated Jul. 12, 2012. cited by applicant .
Non-Final Office Action U.S. Appl. No. 13/131,905 dated Dec. 7,
2012. cited by applicant.
|
Primary Examiner: Bullock; In Suk
Assistant Examiner: Pregler; Sharon
Attorney, Agent or Firm: Foley & Lardner LLP
Claims
The invention claimed is:
1. An olefin production process comprising reacting a ketone and
hydrogen in the presence of at least one dehydration catalyst and
an indium-silver-containing catalyst, the at least one dehydration
catalyst being selected from metal oxide catalysts containing at
least one Group 6 (VIB) element, zeolites, aluminas and heteropoly
acid salts in which part or all the protons in heteropoly acids are
exchanged with metal cations.
2. The olefin production process according to claim 1, wherein the
dehydration catalyst is at least one dehydration catalyst selected
from zeolites, .gamma.-aluminas, tungsten oxide, molybdenum oxide
and heteropoly acid salts in which part or all the protons in
heteropoly acids are exchanged with metal cations.
3. The olefin production process according to claim 1, wherein the
ketone is acetone and the olefin is propylene.
4. The olefin production process according to claim 1, wherein the
heteropoly acid is at least one heteropoly acid selected from
phosphotungstic acid, silicotungstic acid, phosphomolybdic acid and
silicomolybdic acid.
5. The olefin production process according to claim 1, wherein the
heteropoly acid salt is supported on silica.
6. The olefin production process according to claim 1, wherein the
reaction temperature in the reaction is in the range of 50 to
500.degree. C.
7. The olefin production process according to claim 1, wherein the
reaction is catalyzed by a mixture of the dehydration catalyst and
the indium-silver-containing catalyst.
8. The olefin production process according to claim 1, wherein the
ketone is acetone obtained with an isopropyl alcohol-producing
bacterium that produces isopropyl alcohol and acetone from a
plant-derived material, and the olefin is propylene.
Description
TECHNICAL FIELD
The present invention relates to processes for producing olefins by
reacting a ketone and hydrogen. In more detail, the invention
relates to processes for producing olefins with high selectivity
from a ketone and hydrogen as starting materials in a single
reaction step.
In particular, the invention is concerned with processes for
producing propylene by reacting acetone and hydrogen. In more
detail, the invention pertains to processes for producing propylene
from acetone and hydrogen as starting materials in a single
reaction step.
BACKGROUND ART
A reaction between benzene and propylene gives cumene. Oxidation of
cumene results in cumene hydroperoxide. The cumene hydroperoxide is
acid decomposed into phenol and acetone. A combination of these
known reactions is the cumene process which is currently a
mainstream process for the production of phenol.
The cumene process gives acetone as a by-product, and is valuable
when both phenol and acetone are required. However, if the acetone
produced is in excess of demand, the economic efficiency is
deteriorated due to the price difference between acetone and
starting material propylene. Methods have been then proposed in
which by-product acetone is reused as a material in the cumene
process through various reactions.
Acetone is readily hydrogenated to isopropanol. Patent Document 1
discloses a process in which the isopropanol thus obtained is
dehydrated to propylene and the propylene is reacted with benzene
to give cumene, in detail acetone is reused as a material in the
cumene process by being converted to propylene through two reaction
steps.
In the reuse of acetone, an industrial and practical process should
be established which is capable of producing propylene from acetone
with high selectivity. Further, the establishment of industrial and
practical processes capable of producing not only propylene but
other olefins from general ketones with high selectivity is also
valuable in other various processes.
Patent Document 2 discloses a process in which propylene is
obtained through hydrogenation of acetone at 400.degree. C. in the
presence of a catalyst containing Cu (25%), zinc monoxide (35%) and
aluminum monoxide (40%). In spite of the high reaction temperature
of 400.degree. C., however, the acetone conversion is low at 89%.
Further, the propylene selectivity according to this document is
only 89% because of a side reaction hydrogenating propylene to
propane.
CITATION LIST
Patent Literatures
Patent Document 1: JP-A-H02-174737 Patent Document 2: East German
Patent DD84378
SUMMARY OF INVENTION
Technical Problem
It is therefore an object of the present invention to provide a
novel olefin production process that can be established as an
industrial and practical process capable of producing olefins with
high selectivity by directly reacting a ketone and hydrogen in a
single reaction step. In particular, an object of the invention is
to provide a novel propylene production process in which propylene
is obtained with high selectivity by directly reacting acetone and
hydrogen.
Solution to Problem
The present inventors studied diligently to achieve the above
objects. They have then found that olefins are produced with high
selectivity by reacting a ketone and hydrogen in a single reaction
step in the presence of a specific dehydration catalyst and a
silver-containing catalyst.
In particular, it has been found that propylene can be produced in
high yield from acetone and hydrogen as starting materials.
An olefin production process according to the present invention
comprises reacting a ketone and hydrogen in the presence of at
least one dehydration catalyst and a silver-containing catalyst,
the at least one dehydration catalyst being selected from metal
oxide catalysts containing at least one Group 6 (VIB) element,
zeolites, aluminas and heteropoly acid salts in which part or all
the protons in heteropoly acids are exchanged with metal
cations.
In a preferred embodiment, the silver-containing catalyst further
contains at least one Group 13 (IIIA) element.
The dehydration catalyst is preferably at least one dehydration
catalyst selected from zeolites, .gamma.-aluminas, tungsten oxide,
molybdenum oxide and heteropoly acid salts in which part or all the
protons in heteropoly acids are exchanged with metal cations.
In a preferred embodiment, the ketone is acetone and the olefin is
propylene.
The heteropoly acid is preferably at least one heteropoly acid
selected from phosphotungstic acid, silicotungstic acid,
phosphomolybdic acid and silicomolybdic acid.
The heteropoly acid salt is preferably supported on silica.
The reaction temperature in the reaction is preferably in the range
of 50 to 500.degree. C.
The reaction is preferably catalyzed by a mixture of the
dehydration catalyst and the silver-containing catalyst.
The ketone is preferably acetone obtained with an isopropyl
alcohol-producing bacterium that produces isopropyl alcohol and
acetone from a plant-derived material, and the olefin is preferably
propylene.
Advantageous Effects of the Invention
According to the processes of the invention, olefins can be
produced from a ketone and hydrogen as starting materials in a
single reaction step with industrial and practical advantages. In
particular, the novel propylene production processes of the
invention can produce propylene with high selectivity by directly
reacting acetone and hydrogen.
DESCRIPTION OF EMBODIMENTS
In an olefin production process according to the present invention,
a ketone and hydrogen are reacted in the presence of at least one
dehydration catalyst and a silver-containing catalyst. The at least
one dehydration catalyst is selected from metal oxide catalysts
containing at least one Group 6 (VIB) element, zeolites, aluminas
and heteropoly acid salts in which part or all the protons in
heteropoly acids are exchanged with metal cations.
In the present invention, two components are used as catalysts,
namely, a silver-containing catalyst and at least one dehydration
catalyst selected from metal oxide catalysts containing at least
one Group 6 (VIE) element, zeolites, aluminas and heteropoly acid
salts in which part or all the protons in heteropoly acids are
exchanged with metal cations. The catalyst components may be used
in any manner without limitation. In an embodiment, the dehydration
catalyst and the silver-containing catalyst may be physically mixed
on a catalyst particle level with a centimeter size. In another
embodiment, the catalysts may be finely pulverized and mixed
together, and the mixture may be shaped into catalyst particles
with a centimeter size. In a still another embodiment, the
dehydration catalyst may be used as a carrier, and the
silver-containing catalyst may be supported thereon. Alternatively,
the dehydration catalyst may be supported on the silver-containing
catalyst as a carrier.
In the olefin production processes according to the invention, it
is considered that the silver-containing catalyst catalyzes
hydrogenation of the ketone into an alcohol and the dehydration
catalyst catalyzes dehydration of the alcohol to an olefin. When
the ketone is acetone for example, reactions are considered to take
place such that acetone is hydrogenated into isopropyl alcohol
under the catalysis of the silver-containing catalyst and the
isopropyl alcohol is dehydrated by the dehydration catalyst to give
propylene and water.
That is, it is considered that the hydrogenation reaction and the
dehydration reaction take place stepwise in the olefin production
processes of the invention. Accordingly, the catalysts may form
distinct catalyst layers in the appropriate order suited for the
reactions, or the silver-containing catalyst and the dehydration
catalyst may be mixed in a graded mixing ratio.
The ketones used in the invention may be selected appropriately
depending on the target olefins. For example, acetone is used to
produce propylene, and methyl ethyl ketone is used to obtain
1-butene.
The olefin production processes of the invention are suited for the
production of propylene from acetone.
The ketones may be obtained by any methods without limitation. For
example, acetone that is by-produced in the production of phenol,
and methyl ethyl ketone from dehydrogenation of 2-butanol may be
used. When the ketone is acetone, acetone may be used which is
obtained with an isopropyl alcohol-producing bacterium that
produces isopropyl alcohol and acetone from a plant-derived
material.
The plant-derived materials are not particularly limited as long as
they are carbon sources obtained from plants and are metabolized to
isopropyl alcohol by bacteria. The plant-derived materials include
organs such as roots, stems, trunks, branches, leaves, flowers and
seeds, plants or plant organs having these organs, and degradation
products of these plant-derived materials. Further, the term
plant-derived materials in the invention includes carbon sources
obtained from plants, plant organs or degradation products thereof
that can be used as carbon sources by bacteria in culture. Examples
of the carbon sources as the plant-derived materials include sugars
such as starch, glucose, fructose, sucrose, xylose and arabinose,
and plant degradation products and cellulose hydrolysates
containing large amounts of the above sugars. Further, the carbon
sources in the invention include plant oil-derived glycerols and
fatty acids. Preferred plant-derived materials include agricultural
crops such as grain, and corn, rice, wheat, bean, sugarcane, beet
and cotton. These materials may be used in any form without
limitation, and for example may be used in the form of unprocessed
product, squeezed juice or milled product. In an embodiment, the
carbon sources as described above may be used directly.
The isopropyl alcohol-producing bacteria are not limited as long as
they can produce isopropyl alcohol and acetone from the
plant-derived materials. For example, there may be used bacteria
that are cultured on the plant-derived materials and secrete
isopropyl alcohol and acetone in the culture medium after a given
time. Such isopropyl alcohol-producing bacteria are described in
literature such as WO 2009/008377, Chinese Patent Application No.
CN1043956A, JP-A-S61-67493, and Applied and Environmental
Microbiology, Vol. 64, No. 3, pp. 1079-1085 (1998). In particular,
isopropyl alcohol-producing bacteria described in WO 2009/008377
are preferred.
The isopropyl alcohol-producing bacteria described in WO
2009/008377 are given acetoacetic acid decarboxylase activity,
isopropyl alcohol dehydrogenase activity, CoA transferase activity
and thiolase activity.
The words the bacteria are "given" the activities mean that an
enzyme-encoding gene is introduced into the host bacteria from
outside the bacteria, and that an enzyme gene possessed by the host
bacteria on the genome is strongly expressed by enhancing the
promoter activity or replacing the promoter with another
promoter.
In a preferred embodiment, the acetoacetic acid decarboxylase
activity, the isopropyl alcohol dehydrogenase activity, the CoA
transferase activity and the thiolase activity are obtained by the
introduction of a gene that encodes an enzyme derived from at least
one selected from the group consisting of Clostridium bacteria,
Bacillus bacteria and Escherichia bacteria.
In a more preferred embodiment, the acetoacetic acid decarboxylase
activity and the isopropyl alcohol dehydrogenase activity are
obtained by the introduction of a gene that encodes an enzyme
derived from Clostridium bacteria, and the CoA transferase activity
and the thiolase activity are obtained by the introduction of a
gene that encodes an enzyme derived from Escherichia bacteria.
In a particularly preferred embodiment, the acetoacetic acid
decarboxylase activity is obtained by the introduction of a gene
that encodes an enzyme derived from Clostridium acetobutylicum, the
isopropyl alcohol dehydrogenase activity is obtained by the
introduction of a gene that encodes an enzyme derived from
Clostridium beijerinckii, and the CoA transferase activity and the
thiolase activity are obtained by the introduction of a gene that
encodes an enzyme derived from Escherichia coli.
In another preferred embodiment, the acetoacetic acid decarboxylase
activity, the isopropyl alcohol dehydrogenase activity, the CoA
transferase activity and the thiolase activity are each obtained by
the introduction of a gene that encodes an enzyme derived from
Clostridium bacteria.
The isopropyl alcohol-producing bacteria are preferably Escherichia
coli.
The production of isopropyl alcohol and acetone from the
plant-derived materials by the isopropyl alcohol-producing bacteria
usually gives by-products such as water and carboxylic acids. When
acetone obtained from the plant-derived material with the isopropyl
alcohol-producing bacteria is used as the ketone in the invention,
the acetone may be purified to high purity by removing the
isopropyl alcohol, water and other by-products from the
product.
Alternatively, the isopropyl alcohol and acetone in the product may
be concentrated to a high concentration while the by-products are
removed. When such acetone is used in the process of the invention,
the isopropyl alcohol and water will be supplied to a reactor
together with the acetone. The isopropyl alcohol is dehydrated by
the dehydration catalyst, producing propylene and water.
The hydrogen reacted with the ketone in the invention may be a
molecular hydrogen gas or a hydrocarbon such as cyclohexane that
generates hydrogen when subjected to reaction conditions.
Theoretically, the hydrogen may be used at least in an equimolar
amount relative to the ketone. From the viewpoint of separation and
recovery, the hydrogen may be preferably used in an equimolar to
thirty-fold molar amount, and more preferably in an equimolar to
fifteen-fold molar amount relative to the ketone. When the ketone
conversion is desired to be less than 100%, the hydrogen amount may
be controlled less than the equimolar amount relative to the
ketone. In the invention, the hydrogen reacts with the oxygen atom
in the ketone to form water, and the water produced may be
recovered from a reactor outlet. An excess of hydrogen over the
ketone is not substantially consumed as long as undesirable side
reactions do not take place.
The hydrogen gas is generally supplied to a reactor continuously,
but the supply methods are not particularly limited thereto. In an
embodiment, the hydrogen gas may be supplied intermittently such
that the hydrogen is supplied at the initiation of the reaction and
the supply is suspended during the reaction and restarted after a
prescribed time. In the case of a liquid-phase reaction, the
hydrogen gas may be supplied while being dissolved in a solvent. In
a recycle process, hydrogen gas recovered from the column top
together with low-boiling fractions may be resupplied. The pressure
of the hydrogen supplied is generally equal to the pressure in the
reactor, but may be appropriately adjusted depending on the
hydrogen supply methods.
In the invention, the reaction may be carried out by any methods
under any conditions without limitation. Exemplary conditions and
methods are described below.
The contact between the starting materials, i.e., the ketone and
the hydrogen gas, may take place in a gas-liquid countercurrent
flow or a gas-liquid co-current flow. The liquid and gas directions
may be descending liquid/ascending gas, ascending liquid/descending
gas, ascending liquid/ascending gas, or descending
liquid/descending gas.
<Dehydration Catalysts>
In the invention, at least one dehydration catalyst is used which
is selected from metal oxide catalysts containing at least one
Group 6 (VIB) element, zeolites, aluminas and heteropoly acid salts
in which part or all the protons in heteropoly acids are exchanged
with metal cations. The dehydration catalysts may be used singly,
or two or more kinds may be used in combination.
The metal oxide catalysts containing at least one Group 6 (VIB)
element include tungsten oxide and molybdenum oxide.
The zeolites that are inorganic crystalline porous compounds mainly
composed of silicon and aluminum are suitable dehydration catalysts
from the viewpoints of heat resistance and acid strength. Suitable
zeolites may be selected appropriately depending on the molecular
diameter of the alcohols which are considered as intermediates in
the invention and the target olefins.
In detail, zeolites having an eight to sixteen-membered oxygen ring
pore are preferably used.
Examples of the zeolites having an eight to sixteen-membered oxygen
ring pore include chabazite, erionite, ferrierite, heulandite,
ZSM-5, ZSM-11, ZSM-12, NU-87, theta-1, weinbergerite, X-type
zeolite, Y-type zeolite, USY-type zeolite, mordenite, dealuminated
mordenite, f3-zeolite, MCM-22, MCM.sup.-36, MCM-56, gmelinite,
offretite, cloverite, VPI-5 and UTD-1.
Of the zeolites, those having a pore size approximately the same as
the molecular diameter of the alcohols are preferable, and zeolites
having an eight to twelve-membered oxygen ring pore are more
preferable. Examples of the zeolites having an eight to
twelve-membered oxygen ring pore include chabazite, erionite,
Y-type zeolite, USY-type zeolite, mordenite, dealuminated
mordenite, .beta.-zeolite, MCM-22, MCM-56, ZSM-12 and ZSM-5. In the
zeolites, the composition ratio between silicon and aluminum
(silicon/aluminum) is in the range of 2/1 to 200/1, and in view of
activity and heat stability, preferably in the range of 5/1 to
100/1. Further, isomorphously substituted zeolites may be used in
which aluminum atoms in the zeolite skeleton are substituted with
other metal such as Ga, Ti, Fe, Mn or B.
Examples of the aluminas include .alpha.-alumina and
.gamma.-alumina. In particular, .gamma.-alumina is preferably used
from the viewpoints of heat resistance and acid strength of the
dehydration catalyst.
In the heteropoly acid salts used in the invention, part or all the
protons in heteropoly acids are exchanged with metal cations,
namely, at least part of the protons in heteropoly acids are
exchanged with metal cations. In a preferred embodiment, at least
one heteropoly acid is selected from phosphotungstic acid,
silicotungstic acid, phosphomolybdic acid and silicomolybdic acid.
These preferred heteropoly acids are obtainable in the industry.
Preferred metal cations are alkali metal cations and alkaline earth
metal cations. The alkali metal cations are more preferable, and
potassium cation and cesium cation are particularly preferable.
Examples of the heteropoly acid salts include potassium
phosphotungstate, potassium silicotungstate, potassium
phosphomolybdate, potassium silicomolybdate, cesium
phosphotungstate, cesium silicotungstate, cesium phosphomolybdate
and cesium silicomolybdate. In these salts, at least part of the
protons should be exchanged with the metal cations, and all the
protons may be exchanged with the metal cations.
The heteropoly acid salt may be supported on a carrier. Examples of
the carriers include silica, alumina, titania, zirconia,
silica-alumina, silica-titania and silica-zirconia, with silica
being particularly preferable. In a preferred embodiment, the
heteropoly acid salt is supported on silica. The heteropoly acid
salt may be supported on the carrier by known methods, for example
by a method described in JP-A-H06-91171.
In a preferred embodiment, at least one dehydration catalyst is
selected from the zeolites, .gamma.-alumina, tungsten oxide,
molybdenum oxide and heteropoly acid salts in which part or all the
protons in heteropoly acids are exchanged with metal cations. The
heteropoly acid salts are most preferable because undesired side
reactions such as aldol condensation of ketone, olefin
oligomerization and olefin hydrogenation are inhibited.
The shape of the dehydration catalysts is not particularly limited,
and the dehydration catalysts may be in the form of sphere,
cylindrical column, extrudate or crushed particles. The size of the
particles of the dehydration catalysts may be selected in the range
of 0.01 mm to 100 mm depending on the size of a reactor. When the
dehydration catalyst is supported on the carrier, the particle size
of the supported catalyst is preferably in the above range.
The dehydration catalysts may be used singly, or two or more kinds
may be used in combination.
Silver-Containing Catalysts
The silver-containing catalysts in the invention are not
particularly limited as long as the catalysts contain silver
element and function as hydrogenation catalysts.
The silver-containing catalysts may be used singly, or two or more
kinds may be used in combination.
The silver-containing catalysts catalyze the hydrogenation of
ketones but substantially do not function as hydrogenation
catalysts for olefins. Accordingly, paraffins that are by-produced
by hydrogenation of olefins may be reduced compared to reactions
catalyzed by, for example, copper-containing hydrogenation
catalysts. In the case where the ketone is acetone, the production
of by-product propane may be suppressed by the use of the
silver-containing catalyst.
In a preferred embodiment, the silver-containing catalysts further
contain at least one Group 13 (IIIA) element. The Group 13 (IIIA)
elements include aluminum and indium. In particular, the
silver-containing catalyst which further contains indium does not
induce the hydrogenation of the target olefins and thereby can
reduce the by-production of paraffins more effectively.
Examples of the silver-containing catalysts include Ag.sub.2O
(metal oxide), AgCl (metal chloride) and metal cluster compounds
such as Cu--Ag.
The silver-containing catalyst may be supported on a carrier.
Examples of the carriers include silica, alumina, silica alumina,
titania, magnesia, silica magnesia, zirconia, zinc oxide, carbon,
acid clay, diatomaceous earth and zeolite. In a preferred
embodiment, at least one carrier is selected from silica, alumina,
silica alumina, titania, magnesia, silica magnesia, zirconia, zinc
oxide and carbon.
The silver-containing catalyst may be supported on the carrier by
soaking the carrier in an aqueous solution of silver nitrate or the
like and calcining the carrier. Alternatively, silver may be bonded
with an organic molecule ligand to become soluble in organic
solvents, and the carrier may be soaked in a solution of the
silver-ligand complex in an organic solvent and thereafter
calcined. Taking advantage of the characteristic that some of the
complexes are vaporized under vacuum, such complexes may be
supported on the carrier by deposition or the like. Further, a
coprecipitation method may be adopted in which the carrier is
obtained from a corresponding metal salt in the presence of silver
which will form the hydrogenation catalyst and thereby the carrier
synthesis and the supporting of the silver-containing catalyst are
carried out simultaneously.
Commercially available silver-containing catalysts include
Ag-supporting silica catalysts and Ag-supporting alumina catalysts.
The silver-containing catalysts maybe used singly, or two or more
kinds may be used in combination.
The silver-containing catalysts which further contain at least one
Group 13 (IIIA) element may be prepared by, for example, supporting
a Group 13 (IIIA) element on the silver-containing catalyst.
The silver-containing catalysts may achieve higher activity or
selectivity by the addition thereto of metal salts such as
PbSO.sub.4, FeCl.sub.2 and SnCl.sub.2, alkali metals such as K and
Na, alkali metal salts, or BaSO.sub.4. Such metal components may be
added as required.
The shape of the silver-containing catalysts is not particularly
limited, and the silver-containing catalysts may be in the form of
sphere, cylindrical column, extrudate or crushed particles. The
size of the particles of the silver-containing catalysts may be
selected in the range of 0.01 mm to 100 mm depending on the size of
a reactor.
As described hereinabove, the silver-containing catalyst maybe
supported on the dehydration catalyst. For example, the
silver-containing catalyst supported on the dehydration catalyst
may be prepared by soaking the dehydration catalyst in an aqueous
solution of silver nitrate or the like and calcining the
dehydration catalyst. Alternatively, silver may be bonded with an
organic molecule ligand to become soluble in organic solvents, and
the dehydration catalyst may be soaked in a solution of the
silver-ligand complex in an organic solvent and thereafter
calcined. Taking advantage of the characteristic that some of the
complexes are vaporized under vacuum, such complexes may be
supported on the dehydration catalyst by deposition or the like.
Further, a coprecipitation method may be adopted in which the
dehydration catalyst is obtained from a corresponding metal salt in
the presence of silver which will form the silver-containing
catalyst and thereby the carrier synthesis and the supporting of
the silver-containing catalyst are carried out simultaneously.
The reaction temperature in the invention is not particularly
limited, but is preferably in the range of 50 to 500.degree. C.,
and more preferably 60 to 400.degree. C. The reaction pressure is
preferably in the range of 0.1 to 500 atm, and more preferably 0.5
to 100 atm.
The amount of the catalysts is not particularly limited in the
invention. In an embodiment in which the reaction is performed in a
fixed bed flow apparatus, the catalyst amount may be such that the
supply amount (weight) of the starting material (ketone) per hour
divided by the catalyst weight (the total weight of the
silver-containing catalyst and the dehydration catalyst), namely,
the weight hourly space velocity (WHSV) is preferably in the range
of 0.01 to 200 /h, and more preferably 0.02 to 100 /h.
The weight ratio of the dehydration catalyst and the
silver-containing catalyst is not particularly limited, but the
dehydration catalyst:silver-containing catalyst (weight ratio) is
usually in the range of 1:0.01 to 1:100, and preferably 1:0.05 to
1:50. An excessively small weight ratio of the dehydration catalyst
results in insufficient dehydration reaction and low yield of
olefins, causing economic disadvantages. An excessively large
weight ratio of the dehydration catalyst can be uneconomical
because the ketone conversion is lowered.
In the case where the reaction is performed in a fixed bed reactor,
the packing mode of the dehydration catalyst and the
silver-containing catalyst may greatly affect the reaction results.
As described hereinabove, the hydrogenation reaction and the
dehydration reaction probably take place stepwise in the invention.
Accordingly, the catalysts are preferably packed in the appropriate
order suited for the reactions in order to catalyze the reactions
effectively and prevent undesired side-reactions.
In particular, increasing the hydrogen pressure or the reaction
temperature to accelerate the reaction rate usually involves
undesired side-reactions that are not observed at low hydrogen
pressure or low reaction temperature. In such cases, the reaction
results can be greatly influenced by the catalyst packing
manner.
For example, the catalysts may be packed in the appropriate order
suited for the reactions in a manner such that: (1) the dehydration
catalyst and the silver-containing catalyst are mixed together and
the mixture is packed in the reactor; (2) the silver-containing
catalyst forms a layer (on the upstream side) and the dehydration
catalyst forms a layer (on the downstream side); (3) the
dehydration catalyst supporting the silver-containing catalyst is
packed in the reactor; (4) the silver-containing catalyst forms a
layer (on the upstream side), and the dehydration catalyst and the
silver-containing catalyst together form a layer (on the downstream
side); (5) the silver-containing catalyst forms a layer (on the
upstream side), and the dehydration catalyst supporting the
silver-containing catalyst forms a layer (on the downstream side);
(6) the dehydration catalyst and the silver-containing catalyst
together form a layer (on the upstream side) and the dehydration
catalyst forms a layer (on the downstream side); or (7) the
dehydration catalyst supporting the silver-containing catalyst
forms a layer (on the upstream side) and the dehydration catalyst
forms a layer (on the downstream side). Here, the term upstream
side means an inlet side of the reactor, in other words, this term
indicates that the starting materials are passed through the layer
in the first half of the reaction. The term downstream side means
an outlet side of the reactor, in other words, this term indicates
that the materials are passed through the layer in the last half of
the reaction. In an embodiment of the reaction in which the ketone
and hydrogen are contacted in a gas-liquid countercurrent flow, the
inlet side of the reactor indicates an inlet for introducing the
ketone.
In an embodiment for carrying out the invention, the reaction may
be carried out in a diluted reaction system by supplying a solvent
or a gas that is inert to the catalysts and the reaction
materials.
The reaction may be performed by a batch process, a semi-batch
process or a continuous flow process. The reaction phase may be a
liquid phase, a gas phase or a gas-liquid mixed phase. The catalyst
packing modes include fixed bed systems, fluidized bed systems,
suspended bed systems and multistage fixed bed systems.
In the invention, the dehydration catalyst and the
silver-containing catalyst may be dehydrated by known methods.
In the case of fixed bed reaction system, the dehydration catalyst
and the silver-containing catalyst may be dehydrated by being held
at a temperature of 300.degree. C. or above for at least 10 minutes
while passing an inert gas such as nitrogen or helium through the
reactor packed with the catalysts. To develop the activity of the
silver-containing catalyst, the dehydration treatment may be
followed by a treatment under a stream of hydrogen.
In the event that the catalyst activity is lowered after a time of
reaction, the dehydration catalyst and the silver-containing
catalyst may be regenerated by known methods to recover the
activity.
To maintain the yield of olefins, two or three reactors may be
arranged in parallel to adopt a merry-go-round system in which the
catalysts in one reactor are regenerated while the reaction is
continuously carried out in the remaining one or two reactors. When
the process involves three reactors, two of these reactors may be
connected in series to stabilize the production output. When the
reaction is carried out in a fluidized bed flow reaction system or
in a moving bed reaction system, part or the whole of the catalysts
may be withdrawn from the reactor continuously or intermittently
while a corresponding amount of the catalysts is newly added to
maintain the activity at a constant level.
EXAMPLES
The present invention will be described in greater detail by
presenting examples without limiting the scope of the
invention.
Production Example 1
A 300 ml pear shaped flask was charged with 50.0 g of silica gel
(Wakogel C-100, manufactured by Wako Pure Chemical Industries,
Ltd.), 4.77 g of silver lactate (0.5 hydrate) and 100 ml of ion
exchange water. These materials were mixed together using a rotary
evaporator at room temperature for 1 hour. Water was distilled away
at a reduced pressure of 20 mm Hg at 40 to 50.degree. C. Thus,
silver was supported on the silica gel. The silver-supporting
silica gel was subjected to reduction treatment in which the
temperature was increased stepwise from 100.degree. C. to
300.degree. C. in 5 hours under a stream of hydrogen. As a result,
52.5 g of black 5% Ag/silica catalyst was obtained. The 5%
Ag/silica catalyst was sieved to 250 to 500 .mu.m.
Example 1
A fixed bed reaction apparatus was used which was equipped with a
high-pressure feed pump, a high-pressure hydrogen mass flow
controller, a high-pressure nitrogen mass flow controller, an
electric furnace, a reactor having a catalyst-packing part, and a
back pressure valve. A pressurized liquid-phase downflow reaction
was carried out in the reaction apparatus.
The reactor was a SUS 316 reactor having an inner diameter of 1 cm.
The 5% Ag/silica catalyst (classified to 250 to 500 .mu.m) from
Production Example 1 in an amount of 6.0 g was mixed with 0.6 g'of
.beta.-zeolite (manufactured by JGC Catalysts and Chemicals Ltd.,
compacted at 20 MPa and classified to 250 to 500 .mu.m). The
mixture was packed in the reactor from the outlet side to form a
catalyst layer.
The pressure was increased to 3.0 MPa with hydrogen. Under a stream
of hydrogen at 12 ml/min, acetone was passed from the inlet side of
the reactor at a rate of 0.30 g/h at 180.degree. C.
Nitrogen was introduced at 50 ml/min in the middle between the
reactor outlet and the back pressure valve through the
high-pressure nitrogen mass flow controller. GC (a gas
chromatograph) was located in the line downstream from the back
pressure valve, and the reaction products were quantitatively
determined online. The reaction results are set forth in Table 1.
Propylene was produced with good selectivity as shown in Table
1.
Production Example 2
A 300 ml pear shaped flask was charged with 29.1 g of the 5%
Ag/silica catalyst from Production Example 1, 0.43 g of indium
nitrate trihydrate and 100 ml of ion exchange water. These
materials were mixed together using a rotary evaporator at room
temperature for 1 hour. Water was distilled away at a reduced
pressure of 20 mm Hg at 40 to 50.degree. C. Thus, indium nitrate
was supported on the 5% Ag/silica catalyst. The indium-supporting
5% Ag/silica catalyst was subjected to reduction treatment in which
the temperature was increased stepwise from 100.degree. C. to
300.degree. C. in 3 hours under a stream of hydrogen. As a result,
29.2 g of black 5% Ag-0.5% In/silica catalyst was obtained. The 5%
Ag-0.5% In/silica catalyst was sieved to 250 to 500 .mu.m.
Example 2
Reaction was performed in the same manner as in Example 1, except
that the 5% Ag/silica catalyst was replaced by the 5% Ag-0.5%
In/silica catalyst from Production Example 2, and the hydrogen flow
rate was increased from 12 ml/min to 22 ml/min.
The reaction results are set forth in Table 1. Propylene was
produced with good selectivity as shown in Table 1.
Example 3
Reaction was performed in the same manner as in Example 2, except
that the reaction temperature was increased from 180.degree. C. to
240.degree. C.
The reaction results are set forth in Table 1. Propylene was
produced with good selectivity as shown in Table 1.
Example 4
Reaction was performed in the same manner as in Example 2, except
that the reaction temperature was increased from 180.degree. C. to
280.degree. C.
The reaction results are set forth in Table 1. Propylene was
produced with good selectivity as shown in Table 1.
Example 5
Reaction was performed in the same manner as in Example 4, except
that 0.6 g of the .beta.-zeolite was replaced by 1.0 g of
.gamma.-alumina (N611N manufactured by JGC CORPORATION, compacted
at 20 MPa and classified to 250 to 500 .mu.m).
The reaction results are set forth in Table 1. Propylene was
produced with good selectivity as shown in Table 1.
TABLE-US-00001 TABLE 1 Hydrogen/ Selectivity acetone Acetone
(%)/acetone Selectivity (%)/(acetone-IPA-DIPE) Reaction Reaction
(molar conversion IPA DIPE Propylene time temperature ratio) (%)
(%) (%) Propylene Propane dimer Others Ex. 1 80 h 180.degree. C. 6
99.9 7.3 1.4 92.2 5.9 1.9 0.0 Ex. 2 80 h 180.degree. C. 11 73.1
12.7 2.0 92.9 0.0 2.4 4.7 Ex. 3 80 h 240.degree. C. 11 90.3 1.3 0.6
91.6 0.0 1.6 6.8 Ex. 4 80 h 280.degree. C. 11 99.9 0.1 0.1 92.1 0.5
4.8 2.6 Ex. 5 80 h 280.degree. C. 11 99.8 0.3 0.7 83.6 0.6 9.6 6.2
IPA = isopropanol DIPE = diisopropyl ether
Example 6
A fixed bed reaction apparatus was used which was equipped with a
high-pressure feed pump, a high-pressure hydrogen mass flow
controller, a high-pressure nitrogen mass flow controller, an
electric furnace, a reactor having a catalyst-packing part, and a
back pressure valve. A pressurized liquid-phase downflow reaction
was carried out in the reaction apparatus.
The reactor was a SUS 316 reactor having an inner diameter of 1 cm.
The 5% Ag-0.5% In/silica catalyst (classified to 250 to 500 .mu.m)
from Production Example 2 in an amount of 3.0 g was packed through
the outlet of the reactor to form an upstream catalyst layer.
Further, a mixture of 3.0 g of the hydrogenation catalyst and 1.0 g
of tungsten oxide (NO.sub.3) was packed to form a downstream
catalyst layer.
The pressure was increased to 3.0 MPa with hydrogen. Under a stream
of hydrogen at 22 ml/min, acetone was passed from the inlet side of
the reactor at a rate of 0.30 g/h at 300.degree. C.
Nitrogen was introduced at 50 ml/min in the middle between the
reactor outlet and the back pressure valve through the
high-pressure nitrogen mass flow controller. A gas chromatograph
was located in the line downstream from the back pressure valve,
and the reaction products were quantitatively determined online.
The reaction results are set forth in Table 2. Propylene was
produced with good selectivity as shown in Table 2.
Example 7
(Production of Dehydration Catalyst)
H.sub.0.5K.sub.2.5 PW.sub.12O.sub.40 (potassium phosphotungstate in
which the hydrogen atoms in the phosphotungstic acid were partially
exchanged with potassium) in an amount of 2.0 g was added to 15 ml
of ethanol, and the mixture was stirred at 40.degree. C. for 1
hour. Subsequently, 6.9 g of tetraethoxysilane was added thereto
dropwise and the mixture was stirred at 40.degree. C. for 1 hour.
Further, 3.0 g of water was added thereto and the mixture was
stirred at 80.degree. C. for 24 hours. The resultant sol was
evaporated to dryness, and the solid obtained was added to water at
80.degree. C., followed by stirring for 15 hours. The solid was
filtered, washed with water, dried and calcined at 300.degree. C.
to afford a dehydration catalyst in which
H.sub.0.5K.sub.2.5PW.sub.12O.sub.40 was supported on silica in a
weight ratio of 1:1.
(Reaction)
Reaction was performed in the same manner as in Example 6, except
that the tungsten oxide (WO.sub.3) was replaced by 1.0 g of the
above dehydration catalyst (in which
H.sub.0.5K.sub.2.5PW.sub.12O.sub.40 was supported on silica). The
reaction results are set forth in Table 2. Propylene was produced
with good selectivity as shown in Table 2.
Example 8
(Production of Dehydration Catalyst)
A dehydration catalyst in which K.sub.3PW.sub.12O.sub.40 was
supported on silica in a weight ratio of 1:1 was prepared in the
same manner as in Example 7, except that
H.sub.0.5K.sub.2.5PW.sub.12O.sub.40 (potassium phosphotungstate in
which the hydrogen atoms in the phosphotungstic acid were partially
exchanged with potassium) was replaced by K.sub.3PW.sub.12O.sub.40
(potassium phosphotungstate in which all the hydrogen atoms in the
phosphotungstic acid were exchanged with potassium).
(Reaction)
Reaction was performed in the same manner as in Example 6, except
that the tungsten oxide (WO.sub.3) was replaced by 1.0 g of the
above dehydration catalyst (in which K.sub.3PW.sub.12O.sub.40 was
supported on silica). The reaction results are set forth in Table
2. Propylene was produced with good selectivity as shown in Table
2.
TABLE-US-00002 TABLE 2 Hydrogen/ acetone Acetone Selectivity
(%)/acetone Reaction Reaction (molar conversion Propylene time
temperature ratio) (%) IPA DIPE Propylene Propane dimer Others Ex.
6 100 h 300.degree. C. 11 99.9 0.0 0.0 93.4 4.1 1.2 1.3 Ex. 7 100 h
300.degree. C. 11 99.9 0.0 0.0 97.5 0.5 1.7 0.3 Ex. 8 100 h
300.degree. C. 11 99.9 0.0 0.0 98.2 0.5 1.2 0.1 IPA = isopropanol
DIPE = diisopropyl ether
Example 9
(Production of Isopropyl Alcohol and Acetone)
Isopropyl alcohol was produced using isopropyl alcohol-producing
Escherichia coli bacteria (Escherichia coli pGAP-Iaaa/B strain)
described in Example 4 of WO 2009/008377. Here, a production
apparatus 10 as illustrated in FIG. 1 of WO 2009/008377 was used. A
culture tank, a trap tank, an injection tube, a connection tube and
a discharge tube were all made of glass. The culture tank and the
trap tank each had a capacity of 3 L. The trap tank contained 1.8 L
of water as trap liquid (trap water). The trap water had been
cooled to 10.degree. C.
A waste tube was attached to the culture tank, and the increase of
the culture liquid by the feed of sugars or neutralizers was
controlled by appropriately discharging the culture liquid from the
culture tank.
The pGAP-Iaaa/B strain was inoculated in a 100 mL conical flask
that contained 25 mL of LB Broth, Miller culture liquid (Difco
244620) containing 50 .mu.g/mL of ampicillin, and was pre-cultured
overnight with stirring at 120 rpm and a culture temperature of
35.degree. C. The whole amount of the culture liquid was
transferred to the 3 L culture tank (fermentor BMS-PI manufactured
by ABLE & Biott Co., Ltd.) that contained 1475 g of a culture
medium having the composition below. The culture liquid was
cultured with aeration at 1.5 L/min at atmospheric pressure, a
stirring speed of 550 rpm, a culture temperature of 35.degree. C.
and pH of 7.0 (adjusted with an aqueous NH.sub.3 solution). A 45
wt/wt % aqueous glucose solution was added at 7.5 g/L/h for 8 hours
from the initiation of the culture. Afterward, the 45 wt/wt %
aqueous glucose solution was added at 15 g/L/h. The trap water
after 130 hours after the culture initiation was analyzed by GC and
was found to contain 1.6 wt % of acetone and 5.6 wt % of isopropyl
alcohol.
<Culture Medium Composition>
Corn steep liquor (NIHON SHOKUHIN KAKO CO., LTD.): 20 g/L
Fe.sub.2SO.sub.4.7H.sub.2O: 0.09 g/L
K.sub.2HPO.sub.4: 2 g/L
KH.sub.2PO.sub.4: 2 g/L
MgSO.sub.4.7H.sub.2O: 2 g/L
(NH.sub.4).sub.2SO.sub.4: 2 g/L
ADEKA NOL LG126 (ADEKA CORPORATION): 0.6 g/L
Water: balance
Production of Propylene
The aqueous solution containing isopropyl alcohol and acetone (the
trap water after 130 hours from the culture initiation) was
distilled to concentrate isopropyl alcohol and acetone.
In detail, 1947.0 g of the aqueous solution was passed at 500 mL/h
through a column packed with 240 mL of a cation exchange resin
(AMBERLYST 31WET manufactured by ORGANO CORPORATION), thereby
removing residual ammonia. The treated liquid was distilled at
normal pressure to separate fractions having a boiling point of 53
to 81.6.degree. C. Gas chromatography showed that the fractions
contained 22.6 wt % of acetone, 58.7 wt % of isopropyl alcohol and
a balance of water.
Reaction was carried out in the same manner as in Example 8, except
that acetone was replaced by the above mixture liquid containing
isopropyl alcohol, acetone and water, and the amount of the
K.sub.3PW.sub.12O.sub.40-silica catalyst was increased from 1.0 g
to 1.5 g. The reaction results are set forth in Table 3. Propylene
was produced with good selectivity as shown in Table 3.
TABLE-US-00003 TABLE 3 Hydrogen/ acetone Acetone Selectivity
(%)/(acetone + IPA) Reaction Reaction (molar conversion Propylene
time temperature ratio) (%) IPA DIPE Propylene Propane dimer Others
Ex. 9 100 h 300.degree. C. 11 99.9 0.0 0.0 98.0 0.5 1.0 0.5 IPA =
isopropanol DIPE = diisopropyl ether
In Tables 1 to 3, the reaction time indicates the length of time
from the initiation of the reaction after which the reaction
results (acetone conversion, selectivity) were obtained. In detail,
Table 1 shows that the reaction results were obtained after 80
hours after the initiation of the reaction, and Tables 2 and 3 show
that the reaction results were determined after 100 hours after the
initiation of the reaction.
Industrial Applicability
According to the present invention, a ketone and hydrogen are
reacted directly in a single reaction step to yield an olefin with
high selectivity. The processes of the invention thus provide
industrial and practical advantages. By the processes of the
invention, propylene can be obtained directly from acetone that is
by-produced in the production of phenols by the cumene process.
* * * * *